New battery lab scales up from materials to coin and pouch cell tests

The development of battery materials at the University of Eastern Finland began more than a decade ago with research on anode and cathode materials. Now, with the new Battery Research Laboratory at the University of Eastern Finland, battery materials can be studied more comprehensively. "Initially, my research group focused on how to replace the graphite used in anodes of Li-ion batteries with silicon. Today, our research also covers Na-ion batteries and cathode materials," says Professor Vesa-Pekka Lehto from the Department of Technical Physics.

Launched in November last year, the Battery Research Laboratory marks a significant milestone in battery research and development. The new laboratory enables the production of coin and pouch cells, and their performance can be thoroughly tested electrochemically. Using the university's equipment, the structure and characteristics of battery materials can be examined systematically.

"The coin and pouch cells can be either half cells or full cells. This scale is sufficient for studying the performance of various active materials in batteries. In other words, we are not able to test entire battery modules or packs," Lehto notes.

Lehto's research group continues to develop more durable silicon materials for use in Li-ion battery anodes. "At the same time, we aim to improve the performance of NMC cathode materials. One of our guiding principles is to enhance the sustainability of active materials used in batteries. Another interesting line of research is to combine favorable battery and capacitor characteristics in a lithium-ion supercapacitor," he says.

Spanning some 50 square meters, the Battery Research Laboratory can host several researchers working simultaneously. "Currently, we have around 10 people engaged in battery research and development. We hope to double this number in the coming years."

In the laboratory, Master's students specializing in battery technology are taught the core principles of assembling battery cells not only in theory but also in practice, and they also learn the basics of electrochemical testing.

When acquiring equipment for the laboratory, special attention was also paid to supporting university–business collaboration. "If a company has a material whose performance they'd like us to test, the easiest way to do this is through commissioned research. The client will receive a report whose content is agreed in advance. If, on the other hand, a company wants to carry out R&D related to battery materials, the best option is to establish a confidential R&D project," Lehto explains.

Why do batteries need to be developed?

"The green transition will significantly increase the future demand for batteries. It is crucial to succeed in making battery characteristics, such as capacity and charging speed, better for specific applications. This will make electric vehicles, to give an example, more appealing to consumers," Lehto says.

"It is important to understand that different applications emphasize different battery characteristics. A 'one-size-fits-all' battery is therefore unlikely to be developed. At the same time, we must aim for environmentally friendly and low-carbon production of battery materials and cells. Cost plays a major role in consumer acceptance."

At present, Li-ion batteries are by far the most widespread, and their dominance is unlikely to be challenged within the next ten years. Their drawbacks include high cost, relatively modest capacity and a significant carbon footprint.

"Because batteries still almost invariably contain a liquid electrolyte, the risk of ignition is real. This material is between the anode and the cathode, and Li-ions must be able to move through it as easily as possible. Extinguishing battery fires is very challenging. In practice, this is done by cooling the battery," says Lehto.

According to Professor Anna Lähde from the Department of Environmental and Biological Sciences, the next generation of batteries is already here. "The market for Na-ion batteries is growing, and other new battery solutions, such as Li–sulfur batteries, are also expected to enter the market, at scale, around 2030," she says.

"The goal is for future battery solutions to contain no critical metals, but instead to consist of materials such as bio-based carbon structures like hard carbon and sodium. In our joint Utilization of Industrial Side Streams in the Production of Low-carbon Battery Chemicals project, or EKOAKKU for short, we study and develop these types of batteries," she adds.

What, then, would a perfect battery be like?

"One could answer that the battery launched earlier this year by Donut Lab would be close to perfect. If a battery matching their promises could be manufactured on an industrial scale, there would be little need for any other batteries," Lehto concludes.

Provided by University of Eastern Finland